Open AccessPINCH Proteins Regulate Cardiac Contractility by Modulating Integrin-Linked Kinase-Protein Kinase B Signaling
Author(s) -
Benjamin Meder,
Inken G. Huttner,
Farbod SedaghatHamedani,
Steffen Just,
Tillman Dahme,
Karen Frese,
Britta Vogel,
Doreen Köhler,
Wanda Kloos,
Jessica Rudloff,
Sabine Marquart,
Hugo A. Katus,
Wolfgang Rottbauer
Publication year - 2011
Publication title -
molecular and cellular biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.14
H-Index - 327
eISSN - 1067-8824
pISSN - 0270-7306
DOI - 10.1128/mcb.05269-11
Subject(s) - protein kinase b , integrin linked kinase , zebrafish , biology , microbiology and biotechnology , phosphorylation , protein kinase a , contractility , akt1 , kinase , medicine , endocrinology , biochemistry , cyclin dependent kinase 2 , gene
Integrin-linked kinase (ILK) is an essential component of the cardiac mechanical stretch sensor and is bound in a protein complex with parvin and PINCH proteins, the so-called ILK-PINCH-parvin (IPP) complex. We have recently shown that inactivation of ILK or β-parvin activity leads to heart failure in zebrafish via reduced protein kinase B (PKB/Akt) activation. Here, we show that PINCH proteins localize at sarcomeric Z disks and costameres in the zebrafish heart and skeletal muscle. To investigate thein vivo role of PINCH proteins for IPP complex stability and PKB signaling within the vertebrate heart, we inactivated PINCH1 and PINCH2 in zebrafish. Inactivation of either PINCH isoform independently leads to instability of ILK, loss of stretch-responsiveanf andvegf expression, and progressive heart failure. The predominant cause of heart failure in PINCH morphants seems to be loss of PKB activity, since PKB phosphorylation at serine 473 is significantly reduced in PINCH-deficient hearts and overexpression of constitutively active PKB reconstitutes cardiac function in PINCH morphants. These findings highlight the essential function of PINCH proteins in controlling cardiac contractility by granting IPP/PKB-mediated signaling.